- Palladium-Catalyzed Decarbonylative Dehydration for the Synthesis of α-Vinyl Carbonyl Compounds and Total Synthesis of (-)-Aspewentins A, B, and C
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The direct α-vinylation of carbonyl compounds to form a quaternary stereocenter is a challenging transformation. It was discovered that δ-oxocarboxylic acids can serve as masked vinyl compounds and be unveiled by palladium-catalyzed decarbonylative dehydr
- Liu, Yiyang,Virgil, Scott C.,Grubbs, Robert H.,Stoltz, Brian M.
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supporting information
p. 11800 - 11803
(2015/10/05)
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- Efficient Transfer of Chelating Amides into Different Types of Esters and Lactones
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We describe a general and versatile approach for the conversion of carboxylic acid amides into their corresponding esters despite the fact that the former are thermodynamically more stable. The transformations are mediated by the coordination of CuI by a chelating entity. The resulting weakening of the amide bond allows for nucleophilic attack by alcoholic hydroxyl functions. The principle is demonstrated for a wide variety of transformations, leading to different kinds of esters and lactones. Due to their high resonance energy, amides are generally very stable towards solvolysis. However, bispicolylamides can be activated for alcoholysis by an unusual metal coordination involving the electron pair of the amide nitrogen. Herein, we widened the scope of the reaction by transforming the amides into a range of esters and lactones.
- Jakob, Uwe,Mundinger, Stephan,Bannwarth, Willi
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p. 6963 - 6974
(2016/02/18)
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- Substituted guanidine derivatives and process for producing the same
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A compound represented by the general formula (1): wherein each of R1, R2, R3, R4and R5is a hydrogen atom, an alkyl group, a substituted alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, a cycloalkenyl group, a saturated heterocyclic group, an aromatic group, an acyl group or the like; each of Y1, Y2, Y3and Y4is a single bond, —CH2—, —O—, —CO— or the like, provided that at least two of Y1through Y4are independently a group other than a single bond; and Z may be absent, or one or more Zs may be present and are independently an alkyl group, a substituted alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, a cycloalkenyl group, a saturated heterocyclic group, a halogen atom, a carboxyl group, an alkoxycarbonyl group, an aromatic group, an acyl group or the like, is useful as a therapeutic or prophylactic agent for diseases caused by the acceleration of the sodium/proton exchange transport system.
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Page column 66
(2010/01/31)
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